This invention relates to a pipe coupling apparatus and particularly one for temporarily securing together successive lengths of pipe as they are passed through a machine for applying a coating to their outer surface. These machines operate continuously and usually require the pipe to be given a helical or screwing motion either through a nozzle which extrudes a thick coating onto the pipe or-past a chute from which a flexible tape carrying an initially plastic material is wrapped about the pipe. Such devices and their methods of operation are shown in McDonald et 'al. Patent No. 1,988,628.

Those couplers heretofore used in this art ,'such as that of the Boylan et al. Patent No. 1,948,956,

would fulfil in general the requirements of such'a device; namely, tosecure together adjacentlengths of pipe as they passed through the coating machine, and then permit the foremost length, after it had received its coating, to be disengaged and removed to storage or use. These prior devices were found to be satisfactory on-new and perfectly straight pipe, but when crooked or reclaim-- ed or even slightly bent pipe sections were being coupled together the free end of the pipe length already in the helical feed mechanism would whip and oscillate about in such a manner as to prevent the aligning and engagement of the coupler in the succeeding pipe length. oftentimes the protruding jaws would eitherthrow the latter oil its carriage or would engage. improperly and eccentricallyso as to become tightly wedged to gether. Such action was particularly noted when lengths of feet and over were used, andusually 35 required the stopping of the feed and coating mechanism until the coupling elements could be aligned and engaged. This seriously interfered with successful and continuous operation and was particularly objectionable where the engaging elements or jaws of the coupler were relatively few v in number, such as two or four and extended for a relatively long distance from the ends of the pipesto be coupled. I 46 It is an object of this invention to provide a pipe coupling apparatus of this nature which may be easily and positively aligned when used with reclaimed'or crooked pipe.

Another object is to provide a coupler in which the aligning means will be effective t3 operate before the torque transmitting means will become engaged to rotate the length ofpipe being coupled to one already rotating or advancing helically.

Another object is to provide a coupler'in which there are a relatively large number of torque transmitting elements, any group of which may be engaged with its mating group or disengaged therefrom-with a minimum of backlash and shock to the pipe being coupled, or damage to a coating material which may be in place thereon.

, These and other objects and advantages will Figure 1. a

Figure 3 is a sectional view of a pair of engaged lugs on a plane indicated by line IIIIII of Figure 1.

Broadly the coupler comprises a pair of cooperating elements or plugs each adapted to be inserted into the adjacent ends of the pipe sections to be joined. Aligning means are provided to guide the one coupler plug into proper relation with its mate so that a complementary torque transmitting means will engage smoothly and properly, and so that the two pipe sections will be truly alignedduring engagement. Means may be provided in the coupler to cause the leading or foremost pipe section to advance or carry forward the trailing section, as in the Boylan Patent No. 1,948,956, above cited, or some other means independent of the coupler may be utilized to cause the trailing section to be urged forwardly against the one preceding it through the pipe feeding or coating mechanism.

In the example. shown, pipe H1 is the leading, and pipe H is the. trailing section. Plug l2 is inserted in pipe l0, and generally comprises a. plate ll, of substantially the same diameter as pipe in. Means for securing plate iii to pipe ID are provided, in the form of a forwardly extending generally triangular frame l4, whose two apices i5 and i6 bear against the inner surface of the pipe (Figure 2). An adjustable clamp member, such, as set screw l'l, passes through threaded bushing 18, at the third apex of frame It, and may be extended outwardly to secure the plug I! to the pipe ill, or retracted so that the plug may be removed. A stiflenlng'web' l9 may be secured as by welding. to the outer or unsupported edge of frame ll, as" shown.

Plug 20, which is inserted in pipe i I, is similarly fabricated with a plate 2i, frame it, set screw ll and bushing 18. Plates 1! and 2! are each provided with an opening 22, so that access may be had to set screws 1, for operating the same. From this point on, however, the respective constructions of plugs 12 and 20 differ, as will be outlined below. p

Aligning means for the two plugs l2 and 20, in this example, comprise cylindrical rings 23 and 24, as shown in Figure 1. Ring 23 is substantially i0 and extends rearwardly i the diameter of pipe from plate 13 of plug l2. ,Ring 24 is of a suitable outer diameter to be easily received within ring 23, and extends forwardly from plate 2| of plug 20. In operation, it has been found relatively easy to engage or stab ring 24 into ring 23, even 5 though pipe section may be bent, and, due to its rotation or helical movement through a pipe coating machine, maybe oscillating and whipping about its proper position.

The torque transmitting means, by virtue of which the rotation component of the generally helical motion of the driven pipe may be transmitted to the other section, is somewhat similar to a jaw clutch. A plurality of axial lugs 25 extend rearwardiy from plate l3, and are adapted to engage a plurality (usually fewer in num-' ber) of similar lugs 26 extending forwardly from plate 2|. In this example, for a coupling apparatus for twelve-inch pipe, there are twelve lugs 25 and three lugs 26. Preferably, lugs 25 and 26 are shorter, in an axial direction, than rings 23 and 24, so that alignment of the two sections of the coupler will be insured before the lugs engage. A stiifening ring 2l is preferably welded to the inner edges of lugs 25 to strengthen and support them. Aligning ring 24 serves the same purpose for lugs 26.

If it is desired to have the coupler plugs l2 and 20 also act to hold the pipe sections I 0 and il together longitudinally, that is, to prevent their longitudinal separation, lugs 25 and 26 may be provided, respectively, with interlocking hooks 28 and 29 at their engaging ends as shown in Figure 3. Those hooks 28, on lugs 25 of plug I2, which plug is in the leading pipe Ill, face in the direction of the rotation of that pipe and engage hooks 29 on lugs 26 to carry the trailing plug 20 and pipe section I I along through the usual pipe feeding and coating mechanism. However, as soon as the point at which the helical force is applied to pipe I6 is passed by the coupler, pipe ll then receives that force and simply pushes along the preceding pipe l0. Thus the previous torque, which acted to engage hooks 28 and 29, is now reversed, by virtue of the frictional drag of the preceding pipe section III, disengaging hooks 28 and 29 and permitting a slight relative rotation between plugs l2 and 20 as lugs 25 and 26 pass through the angle determined by their spacing, and assume the back-to-back position 50 shown in Figure 2.

Thereafter, when the completely coated pipe section III has emerged from its coating operation, plug l2 may be withdrawn from plug 26 by a simple axial or longitudinal motion, and pipe 55 section It taken out of the path of the following section II, which is meanwhile pulling along a third section of pipe through the equipment byvirtue of a second coupler similar to the one Just described.

As stated above, this latter construction, using hooks 26 and 29 on lugs' 25 and 26, respectively, is optional and is not necessary to the advantageous use of the invention, which is believed to reside in the combination of the aligning and 65 torque transmitting means. Therefore, while a specific construction embodying this invention has been described and illustrated, it is to be understood that the invention is not limited to that specific device, and all such modifications 70 and changes as come within the scope of the appended claims are embraced thereby.

I claim:

1. A coupling for temporarily securing together sections of pipe comprising a pair of plugs adapt- 75 ed to engage the pipes, complementary means on said plugs to align the same, and means fixed with regard to said complementary aligning means for transmitting a torque in either direction from one plug to the other.

2. A coupling for temporarily securing together sections of pipe, comprising a pair of plugs adapted to engage the pipes, a pair of axially extending concentric rings, one on each plug, to align the same, and a plurality of mutually engaging lugs fixed to each of said plugs for transmitting torque from one plug to the other.

3. A coupling according to claim 2, with the addition of means on the lugs of one of said plugs to transmit an axial force to a corresponding means on the lugs of the other of said plugs.

4. A coupling according to claim 2, in which one of said concentric rings extends beyond said lugs so that said rings are effective to align said plugs, and the pipes in which said plugs are engaged, before said lugs are effective to transmit torque from one plug to another, during assembly of said coupling.

5. A coupling for temporarily securing together sections of pipe comprising a pair of plugs adapted to engage the pipes, complementary means on said plugs to align the same, and means fixed with regard to said complementary aligning means for transmitting a torque from one plug to the other, said aligning means extending axially from said plugs through a greater distance than said torque transmitting means so that said aligning means are adapted to be engaged in advance of said torque transmitting means when assembling the parts of said coupling.

6. A coupling for temporarily securing together sections of pipe comprising a pair of plugs adapted to engage the pipes, complementary means on said plugs to align the same, and means fixed with regard to said complementary aligning means for transmitting a torque from one plug to the other. said aligning means comprising a pair of axially extending concentric members.

7. A coupling for temporarily securing together sections of pipe comprising ,a pair of plugs adapted to engage the pipes, complementary means on said plugs to align the same, and means fixed with regard to said complementary aligning means for transmitting a torque from one plug to the other, said aligning means/comprising a pair of axially extending concentric members, the outermost of said members being substantially thesame diameter as the pipe to be coupled.

8. A coupling for temporarily securing together sections of pipe comprising apair of plugs adapted to engage the pipes, complementary means, on said plugs to align the same, means fixed with regard to said complementary aligning means for transmitting a torque from one plug to the other, and complementary means on said plugs for preventing longitudinal separation of said plugs while one ofsaid plugs is being positively advanced helically in a given direction and the other of said plugs is trailing with a corresponding movement.

9. A coupling for temporarily securing together sections of pipe comprising a pair of plugs adapt- WIILIAM n. POS'ILEWAITE. v